IS version

[scalesusa]

I received my new 100-400mmL ISlens today, the 2 stop IS is a big step down from my 70-200mm F/4 L. I can stack TC's on it and get totally stabilized images that are sharper than my 100-400mm IS at 400mm. My 100mmL is yet another step up in IS efficency.


I have been hampered by rain and snow as well, so I only had a hour or two before bad weather hit us.


The lens is really nice, and the IS does work, but I got a few blurry images at relatively fast shutter speeds that never would have happened with my newer technology lenses.





I'll be testing some more, but, if I can just put a 2x TC on my 100-200mm F/4 L IS and get sharper images, the 100-400mm goes back.


I picked up a very nice 600mm f/4 L non is yesterday locally, so I am anxious to try it as well. The first few shots came out well with no TC, but with TC's, I struggled to get sharp images. I haven't yet used a remote shutter release or mirror lockup, I'm waiting for good enough weather to spend some time learninng both.

[neuroanatomist]

enjoy it,and let us see some images when the weather will be better

Nearly 70 °F outside now! []


Here's a 100% crop ofa shot from this morning:





EOS 7D, EF 100-400mm f/4.5-5.6<span style="color: red;"]L IS USM @ 400mm, 1/160 s, f/5.6, ISO 200


Seems pretty sharp to me, even with pixel peeping. [] At 400mm (640mm FF angle of view), this shot at 1/160 s should be pretty blurry due to camera shake. Admittedly, I had a cooperative and relatively still bird or else 1/160 s would likely not have been enough to freeze the subject motion. But it seems the IS is doing a pretty good job!


The other thing to keep in mind is that IS takes a while to stabilize the image (at least half a second, sometimes up to a full second). So, if you just press the shutter button halfway (or the AF-ON button in my case), wait for focus confirmation, then shoot, you won't be getting a stabilized image because AF occurs much faster than the time it takes the IS to fully kick in.

[adrian mandea]

I've noticed the IS delay ,it is slow to activate.Today I was doing some shots in the house with the tamron extender attached and I've noticed that sometimes when I prees the shutter button to take the picture the image jumps (right in that moment)and ruins the picture,but I think this is due to the extender not the lens.





again, enjoy your tele and keep shoting





adrian

[neuroanatomist]

I'll be testing some more, but, if I can just put a 2x TC on my 100-200mm F/4 L IS and get sharper images, the 100-400mm goes back.

If you put a 2x TC on a 70-200mm f/4L IS, you'll have a 140-400mm f/8 lens:


1) It's a stop slower than the 100-400mm - there goes the advantage of the 70-200mm's 3-stop IS vs. the 100-400mm's 2-stop IS.


2) At f/8 it will only autofocus on a 1-series body. (If you're using a 3rd party TC, it will still AF, but AF performance will be negatively impacted.)

[scalesusa]

My new 100mm-400mm L arrived two days ago.My first impressions were that theIS on it is no where near as good as the 70-200mm f/4 ISwith 2X TC.


I'm still waiting for better weather to do a side by side comparison. The 100-400mm lens is excellent, with better than expected contrast, and the IS is very usable, just a step down.


It could be that my 70-200mm F/4 is a exceptional sample, it continues to amaze me. I also just got a 600mm F/4 a couple of days ago, so I'm anxious to get better weather. I took it outside, and set it all up with the Wimberly, etc, and immediately it began to blow and snow. My first impressions of it is that using a TC is extremely difficult, even with a very fast 1/2000 shutter speed and much care to minimize shake. However, I will need time to learn its limitations.


I spotted several eagles, hawks, a vulture, a coyote, and lots of ravensall feasting on a deer carcass yesterday. I used my 100-400 from the car window, but it was just too far away to get anything good. The100% crop was not very sharp, nowhere near what my 70-200mm is with a 2x.


I went back 1.5 hours later, with the 600mm and 2 TC's and tried combinations of 2X and stacked, only with 1.4 + 2 XTC's stacked was I able to get a reasonable size image, but they were not sharp at all. Too slow of a shutter speed, too much fog or mist in the air. Unfortunately,I could not get closer. So i'm still waiting for good weather.